The minimum fee for cryonic preservation is about £17,500. Photograph: John Lamb/Getty Images

Would you be alarmed at the prospect of waking up in the future and finding Simon Cowell lying next to you? Paying to be deep frozen when you die in the hope you will be brought back to life in the future is the stuff of a thousand science fiction stories, films and TV shows.

However, it's not just a few eccentric American millionaires and celebrities keen to cheat death who are putting their faith in cryonics, the process whereby a body (or in some cases just a head) is suspended in liquid nitrogen to preserve it indefinitely, the aim being that – perhaps several decades from now – technology will be available to revive the individual and restore them to good health.

Scores of Brits have also signed up for what the movement has dubbed "a second chance at life", including Victoria Stevens, a 38-year-old mother of two living in North Yorkshire, and Paul Crowley, a 42-year-old computer programmer from south London. They are both members of the US-based Cryonics Institute, which has more than 100 people in "cryonic suspension" at its facility in Michigan.

Simon Cowell is reported to have signed up for cryonic preservation. Photograph: Rex Features

If you want to join them in taking a ride in this so-called "ambulance to the future" but you haven't got Cowell's millions, there are financial advisers who can arrange special life insurance policies that will pay for you to make this trip into the unknown.

The cost of cryonics varies hugely, with a bewildering range of tariffs, fees and add-ons. The Cryonics Institute's minimum fee for cryopreservation is $28,000 (£17,500) – there are other costs on top of this, notably paying for someone to arrive at the scene when you are dying or dead to prepare your body and ship it to America. Alcor, meanwhile, requires people to guarantee a minimum level of funding for its service, which is currently $80,000 (£50,000) for "neurocryopreservation" (the head only) and $200,000 (£125,000) for the whole body. A Russian company called KrioRus, meanwhile, offers a service starting at $12,000 (£7,500), though admits that as it is based in Moscow its services to foreign clients "are more complicated and expensive". The most common way of paying is via life insurance, which spreads the cost over many years.

"Many people probably think cryonics is just for the wealthy, but with life insurance it is affordable for people on a modest income, especially if they start the policy when they are young," says Stevens, from Whitby, who is studying for a natural sciences degree.

Victoria Stevens: 'death seems like an awful waste'

So why did she decide to get involved with cryonics? "I really enjoy being alive," she replies. "I think the prospect of death … it just seems like an awful waste after people spend their lives learning and progressing. I'd like to live longer and see more and experience more. We are happy to prolong our lives with heart transplants and so on – it's just one step on from that." She says there were a "range of reactions" when she told friends and family: some were surprised, though many were supportive. "It's not for everybody," she says, adding: "It is a gamble; it's not a certainty that this will work." She estimates there are about 70-80 UK members of the Cryonics Institute.

Stevens took out a £100,000 insurance policy from insurer PruProtect to fund the process, for which she pays about £36 a month – the premium increases each year in line with inflation. She says it seemed prudent to buy more than the absolute minimum amount of cover because you can probably add another £20,000 or so, on top of the Cryonics Institute's minimum fee, for "standby assistance" – the people who deal with the body the moment someone is legally dead – and the cost of transportation over to the US.

Like many Brits involved in the process, Stevens is also a member of Cryonics UK, an organisation which describes itself as "Britain's volunteer standby assistance team", with its own ambulance and specialist equipment. The aim is that when you are dying, the Cryonics UK team arrive at the scene and, as soon as you are legally dead, take custody of your body, cooling it down and administering various fluids before ensuring it is shipped to the cryonics storage company.

Its not clear what happens if the next of kin object to this happening.

Fellow Briton Paul Crowley, also a member of Cryonics UK, says that his aim is simply either "to not die" or enjoy a vastly longer lifespan. He pays £33 a month for a Prudential insurance policy that provides £60,000 of cover.

Both Crowley and Stevens used Devon-based Unusual Risks Mortgage & Insurance Services, a firm of financial advisers specialising in products for people with medical conditions and "unusual circumstances" that has become the go-to UK organisation for those looking to fund cryonics.

Some of these people had tried other firms but "nobody had taken them very seriously", says Chris Morgan, lead financial adviser at the firm, which now has about 20 cryonics clients, gained through word of mouth.

Most people opt for between £60,000 and £100,000 of cover and, because they are planning for an amount they will need at some unknown point in the future, when prices for cryonics services may be higher, they need to think about inflation-proofing, Morgan says.

He generally recommends "whole of life" cover, which is designed to provide a guaranteed payout on death. The insurance has to be written in a certain way because there needs to be a mechanism in place so the cryonics provider knows it is definitely going to get its money, Morgan says. It is best to use an insurer that provides an "absolute trust" document, where the beneficiary – the cryonics company – is named, and this cannot be changed, he adds. "They need to be absolutely certain they are going to be paid for the services they are providing."

While the likes of Cowell (allegedly) continue to be a cheerleader for cryonics – he reportedly told GQ magazine in 2011 that he was going ahead with it, on the grounds that "if it's possible, and I think it will be, why not have a second crack? Does that sound crazy?" – many others take the view that it's a scam or rip-off.

Woody Allen and Diane Keaton in Sleeper. Photograph: BFI

Woody Allen's comedy Sleeper, where the nerdy owner of a health food shop is cryogenically frozen and defrosted in 2173, probably didn't help those who want the technology to be taken seriously.

Cryonics sceptics include the American science writer Michael Shermer, who wrote a few years ago that cryonics "is too much like religion: it promises everything, delivers nothing (but hope) and is based almost entirely on faith in the future … it dwells in that fuzzy region of claims that have yet to pass any tests but have some basis, however remote, in reality. It is not impossible for cryonics to succeed; it is just exceptionally unlikely".

For those who are interested or tempted, Cryonics UK is holding a "roadshow event" on 28-29 September at Rowland Brothers funeral directors in Whitehorse Road, Croydon. To find out more go to cryonics-uk.com/roadshow.html.

• Tomorrow's Guardian Money section is a "cost of dying" special, covering everything from probate and writing a will to dying intestate and inheritance tax